Flexibility not just complexity
September 1st 2004 Ian Clay, editor of IP&E attended the recently held World launch of the Commander SK AC drive range from Control Techniques
The result of two years intensive development is the Commander SK range of AC drives from Control Techniques. Phil Sewell, executive vice preseident sales and marketing says of the range that “It’s designed to encompass the needs of the mainstream distribution and OEM markets, with the easiest possible installation and set-up that take in some 80% of applications.
“Yet, scratch the surface and there’s a very smart, versatile product that is also suitable for more complex system applications. Its compact size per kW, small footprint, easy set-up, pricing and application versatility adds up to set a new benchmark.”
The first phase of the launch covers sizes A, B and C, up to 4kW. The second phase will introduce larger sizes up to 110kW with an introduction over the next year.
Feature packed As standard the Commander SK is simple to fit and can be programmed for most tasks in a matter of minutes, inputting just 10 basic parameters on the frountmounted keypad. This is one of many unusual features that have been designed into the range to meet end user demands of ease of use and versatility. Copying parameters from one unit to another is made simple with SKs SmartStick plug-in option. The product’s size allows high installation density, saving on control cubicle size and installed cost.
Commander SK, despite its ‘simple and compact’ claims is packed with features that reflect its benchmark status in the general purpose drives market – dynamic braking, ModBus, PID Control, EMC filter, fieldbus options, extensive memeory, basic closed loop and positioning control – even task scheduling. Compact dimensions are supplemented by easy DIN rail mounting in sizes A and B (up to 1.5kW).
Commander SK features easy to use power terminals even for the smallest size unit and all sizes have an internal braking chopper available across the range for easy dynamic braking when an external braking resistor is connected. There is substantial control terminal fucntionality, with five digital inputs, one digital output, 4-20mA or 0-10V analogue inputs that allow PID control, a +10V reference, two relays, a 10 0-10V analogue output a 24V back-up and ModBus RTU as standard. An open protocol for use with PC tools such as Control Techniques’ CT Soft (supplied free with each drive). The drive also includes an internal EMC filter as standard – meeting EN61800-3 regulations.
It has a full range of fieldbus options using SM plug-in modules (interchangeable with CT’s Unidrive SP range) – PROFIBUS-DP, DeviceNet, CANbus, CANopen, Modbus RTU, INTERBUS, CTNet and Ethernet which encompasses Modbus TCP/IP, Ethernet IP and HSE. With extra functionality available via a plug-in I/O option module and an encoder to give basic closed loop speed control and simple positioning, Commander SK can take on complex tasks if required. It even has a timer I/O module with real time clock for simple stand alone task scheduling. This module also accepts encoder speed feedback. Finally, Commander SK even offers simple PLC fucntionality using a Logic-Stick with SyPT Lite programming – to replace a nano or micro PLC, or to replace relays and timers.
Keypads and programming Another feature that came from CT’s hundreds of customer interviews is the choice of two keypad display units, both designed for external panel mounting. The LCD Keypad Plus that hosts many features including a multi-language option connects to the Commander Sk’s Modbus RTU port. Alternatively, users can opt for the simpler LED version. A Smart Stick inserts in the front of the drive to save the set parameters and can be used to clone other drives or to save maintenance time if a drive needs to be changed. For OEM’s, it means that a drive only needs to be set up once, thereafter, the process takes a matter of seconds.
The new Commander SK AC drive range offers so much flexibility to the customer that CT is saying that ‘One day all simple drives will be like the Commander SK’. To quote Dr Bill Drury, executive vice president of technology for CT “We have produced a very flexible and capable product but the essential message is simplicity. Flexibility needn’t necessarily mean complexity.” More articles from Control Techniques: | 
